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991.
The objective of the present study is to improve iron bioavailability using high-density gastroretentive pellets of zero valent iron nanoparticles (ZVINPs). ZVINPs were prepared by the chemical reduction method and were characterized for surface morphology, surface charge, and thermal properties. High-density gastroretentive pellets of iron nanoparticles were prepared using spheronization technique. Pellets were characterized for its micromeritic properties, in vitro drug release, and ex vivo permeability. The pharmacokinetic parameters, organ distribution, and toxicity of the optimized pellets were investigated in Wistar rats. In vivo results revealed more than 2-fold increases in oral bioavailability of iron by pellets compared to plane ferrous sulfate. Toxicological studies of the carriers indicated no evidence of liver damage in acute treatment; however, few complications were observed in chronic treatment groups. These results indicated that ZVINPs pellets successfully improve the oral iron bioavailability but need to obtain more information on repeated dose toxicity to initiate the clinical evaluation of investigational products.  相似文献   
992.
Objective: Treatment intensification with additional anti-diabetic agents is recommended in type 2 diabetes (T2D) for patients inadequately controlled on metformin monotherapy. The present network meta-analysis (NMA) evaluated comparative efficacy and safety of once-weekly semaglutide and sodium-glucose co-transporter 2 inhibitors (SGLT-2is) in T2D patients inadequately controlled with metformin.

Methods: Randomized controlled trials with ≥20 weeks duration were searched in EMBASE, MEDLINE, and CENTRAL. Primary efficacy outcomes were: change from baseline in HbA1c, weight, systolic blood pressure (SBP), post-prandial blood glucose (PPG), and fasting blood glucose (FPG). Treatment effects at 26 (±4) weeks were compared using Bayesian NMAs. Meta-regression and sensitivity analysis were used to address the trial heterogeneity.

Results: Eight trials were found eligible for this NMA. Statistically significant reductions in HbA1c were observed with both 1.0?mg and 0.5?mg doses of once-weekly semaglutide when compared to SGLT-2is. The mean differences in change from baseline in HbA1c for once-weekly semaglutide 1.0?mg vs SGLT-2is ranged from ?0.66% for canagliflozin 300?mg (95% Credible Intervals [CrI]: ?0.82, ?0.50%) to ?1.11% for dapagliflozin 5?mg (95% CrI: ?1.37, ?0.85%). Once-weekly semaglutide 1.0?mg performed significantly better than all SGLT-2is of interest in reducing weight and improving FPG levels: however, SBP reduction was not statistically differentiable. Results of sensitivity analysis and meta-regressions aligned with base-case results. NMAs were not possible for PPG and safety outcomes, due to lack of data.

Conclusion: Once-weekly semaglutide treatment is significantly better compared to SGLT-2is in achieving adequate glycemic control in T2D patients inadequately controlled with metformin monotherapy.  相似文献   
993.

Purpose

Biotherapeutics can be susceptible to oxidation during manufacturing and storage. Free L-methionine is known to protect methionine residues in proteins from oxidation. Similarly, free tryptophan and other indole derivatives have been shown to protect tryptophan residues from oxidation. N-acetyl-DL-tryptophan was previously identified as a potentially superior antioxidant to tryptophan as it has a lower oxidation potential and produces less peroxide upon light exposure. This study sought to confirm the antioxidant efficacy and safety of N-acetyl-DL-tryptophan and L-methionine as formulation components for biotherapeutic drugs.

Methods

Antibodies were subjected to AAPH and light exposure in the presence of N-acetyl-DL-tryptophan and L-methionine. Oxidation in relevant CDR and Fc residues was quantified by peptide map. In silico, in vitro, and in vivo studies were performed to evaluate the safety of N-acetyl-DL-tryptophan and L-methionine.

Results

Peptide mapping demonstrated that N-acetyl-DL-tryptophan was effective at protecting tryptophans from AAPH stress, and that the combination of N-acetyl-DL-tryptophan and L-methionine protected both tryptophan and methionine from AAPH stress. The safety assessment suggested an acceptable safety profile for both excipients.

Conclusions

N-acetyl-tryptophan and L-methionine effectively reduce the oxidation of susceptible tryptophan and methionine residues in antibodies and are safe for use in parenteral biotherapeutic formulations.
  相似文献   
994.
The tripeptide sequence asparagine‐glycine‐arginine (NGR) specifically recognizes aminopeptidase N (APN or CD13) receptors highly expressed on tumor cells and vasculature. Thus, NGR peptides can precisely deliver therapeutic and diagnostic compounds to CD13 expressing cancer sites. In this regard, 2 NGR peptide ligands, HYNIC‐c(NGR) and HYNIC‐PEG2‐c(NGR), were synthesized, radiolabeled with 99mTc, and evaluated in CD13‐positive human fibrosarcoma HT‐1080 tumor xenografts. The radiotracers, 99mTc‐HYNIC‐c(NGR) and 99mTc‐HYNIC‐PEG2‐c(NGR), could be prepared in approximately 95% radiochemical purity and exhibited excellent in vitro and in vivo stability. The radiotracers were hydrophilic in nature with log P values being ?2.33 ± 0.05 and ?2.61 ± 0.08. The uptake of 2 radiotracers 99mTc‐HYNIC‐c(NGR) and 99mTc‐HYNIC‐PEG2‐c(NGR) was similar in nude mice bearing human fibrosarcoma HT‐1080 tumor xenografts, which was significantly reduced (P < .05) during blocking studies. The 2 radiotracers being hydrophilic cleared rapidly from blood, liver, and intestine and were excreted through renal pathway. The pharmacokinetics of 99mTc‐labeled HYNIC peptide could not be modulated through introduction of PEG2 unit, thus posing a challenge for studies with other linkers towards enhanced tumor uptake and retention.  相似文献   
995.
A series of 2‐oxo‐2‐phenylethylidene linked 2‐oxo‐benzo[1,4]oxazine analogues 17a–x and 18a–o , incorporated with a variety of electron‐withdrawing as well as electron‐donating groups at ring A and ring C, were synthesized under greener conditions in excellent yields (up to 98%). These analogues 17a–x and 18a–o were evaluated for their arachidonic acid (AA)‐induced platelet aggregation inhibitory activities in comparison with the standard reference aspirin (IC50 = 21.34 ± 1.09 µg/mL). Among all the screened compounds, eight analogues, 17i , 17x , 18f , 18g , 18h , 18i , 18l , and 18o , were identified as promising platelet aggregation inhibitors as compared to aspirin. In addition, cytotoxic studies in 3T3 fibroblast cell lines by MTT assay of the promising compounds ( 17i , 17x , 18f–18i , 18l , and 18o ) were also performed and the compounds were found to be non‐toxic in nature. Furthermore, the results on the AA‐induced platelet aggregation inhibitory activities of these compounds ( 17i , 17x , 18f–18i , 18l , and 18o ) were validated via in silico molecular docking simulation studies. To the best of our knowledge, this is the first report of the identification of non‐peptide‐based functionalized 2‐oxo‐benzo[1,4]oxazines as platelet aggregation inhibitors.
  相似文献   
996.
A series of N‐(2‐(3,5‐dimethoxyphenyl)benzoxazole‐5‐yl)benzamide derivatives ( 3am ) was synthesized and evaluated for their in vitro inhibitory activity against COX‐1 and COX‐2. The compounds with considerable in vitro activity (IC50 < 1 μM) were evaluated in vivo for their anti‐inflammatory potential by the carrageenan‐induced rat paw edema method. Out of 13 newly synthesized compounds, 3a , 3b , 3d , 3g , 3j , and 3k were found to be the most potent COX‐2 inhibitors in the in vitro enzymatic assay, with IC50 values in the range of 0.06–0.71 μM. The in vivo anti‐inflammatory activity of these six compounds ( 3a , 3b , 3d , 3g , 3j , and 3k ) was assessed by the carrageenan‐induced rat paw edema method. Compounds 3d (84.09%), 3g (79.54%), and 3a (70.45%) demonstrated significant anti‐inflammatory activity compared to the standard drug ibuprofen (65.90%) and were also found to be safer than ibuprofen, by ulcerogenic studies. A docking study was done using the crystal structure of human COX‐2, to understand the binding mechanism of these inhibitors to the active site of COX‐2.
  相似文献   
997.

Background

Dietary habits formed during youth may result in the development of obesity and chronic diseases in adulthood. We aimed to determine the frequency of the consumption of foods and beverages and the degree of adherence to Canada's Food Guide recommendations among multi‐ethnic youths.

Methods

Participants were recruited from 12 schools in the Edmonton, Alberta area by use of posters, school newsletters and advertisements. A 30‐item food frequency questionnaire was administered by a trained interviewer to assess dietary intake in a convenience sample of 557 (328 females and 229 males) youths aged 11–23 years; for the purpose of the present study, only the 14–18 years age group was considered in the analysis. Participants were divided by sex and self‐identified ethnicity into four groups [Indigenous, African & Middle Eastern (AME ), Asian, and European]. Statistical analysis of the data was undertaken using t ‐tests, Welch's analysis of variance and Games‐Howell tests. P  < 0.05 was considered statistically significant.

Results

Vegetables and Fruit recommendations were the least likely to be followed, with 90.7–96.8% of participants in all groups not consuming the recommended number of servings day–1. The mean frequency of fruit consumption was lower among Indigenous youths compared to Asian youths (0.90 versus 1.37 times day–1). A greater proportion of males than females (55.9% versus 44.3%) did not meet the minimum recommendations for Meat and Alternatives (P  = 0.016). The percentage of youths not adhering to recommendations for Milk and Alternatives was 81.7% for Indigenous, 73.3% for AME , 78.6% for Asian and 63.5% for European youths. Indigenous youths more frequently consumed potato chips and soft drinks compared to other ethnic youths. The most frequently consumed beverage was milk (1.25 times day–1).

Conclusions

The majority of youths did not consume minimum daily recommended servings of Vegetables and Fruit, Milk and Alternatives, and/or Meat and Alternatives food groups. Evidence‐based dietary interventions and public health strategies are needed.
  相似文献   
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